Potentiometer output function transmitting means



June 6, 1961 N. WAIL 2,987,634

POTENTIOMETE'R OUTPUT FUNCTION TRANSMITTING MEANS Filed May 8, 1959 PARTRANGE DEVICE r FULL RANGE DEVICE INVENTOR.

NORMAN WA /L HITOIQ/VE) United States Patent 2,987,634 POTENTIOMETEROUTPUT FUNCTION TRANSMITTING MEANS Norman Wail, Ridgefield, N.J.,assignor to The Bendix Corporation, a corporation of Delaware Filed May8, 1959, Ser. No. 811,926 4 Claims. (Cl. 307-149) The invention relatesto an improved system for transmitting a function and part of thatfunction through a pair of potentiometers and a novel rotary segmentalswitch for switching in the part function potentiometer in relation tothe operation of the other or full range potentiometer.

In many computer designs, there exists the problem of transmitting afunction and a part of that function through the operation of a pair ofotentiometers. Thus, for example, one of the potentiometers may berequired to transmit a function from units 0 to 10 and another of thepotentiometers may be required to transmit a part of that functionbetween the units 4 to 6.

An object of the invention is to provide novel and improved means foreffecting the transmission of such functions through a novel circuitarrangement of the respective potentiometers in cooperative relationwith a rotary segmental switch driven in timed relation with the twopotentiometers and arranged so as to switch in and out of operation thepart function transmitting potentiometer to effect the predeterminedpart function output.

Another object of the invention is to provide improved and novel meansfor transmitting a full range output function, together with other meanscooperating therewith for transmitting a part function.

These and other objects and features of the invention are pointed out inthe following description in terms of the embodiment thereof which isshown in the accompanying drawing. It is to be understood, however, thatthe drawing is for the purpose of illustration only and is not adefinition of the limits of the invention, reference being had to theappended claims for this purpose.

The drawing is a schematic wiring diagram of a system in which theinvention is embodied.

Referring to the drawing, there is indicated by the numeral 1 apotentiometer for obtaining a full range output. The potentiometer 1includes a variable resistor element 3 connected across a suitablesource of electrical energy or alternating current 5 and an outputrotary contact arm 7 cooperating with the variable resistor element 3and connected through an electrical conductor 9 to an input of a fullrange controlled device 10 of a computer or other suitable deviceoperated thereby and having an opposite input connection 11.

A second potentiometer 12 may be used for obtaining a part functionoutput. The potentiometer 12 includes a variable resistor element 14connected across the source of alternating current 5 or other suitablesource of electrical energy through fixed resistor elements 16 and 18,together with an output rotary contact arm 20 cooperating with thevariable resistor element 14 and connected through an electricalconductor 22 to a switch segment 24 of a rotary switch 26 for switchingin and out of operation the part function output developed by thepotentiometer 12.

The rotary switch 26 includes the switch segment 24 and additionalswitch segments 28 and 30, together with a rotary switch arm 32cooperating with the switch segments 24, 28 and 30 and connected throughan electrical conductor 34 to an input of a part range controlled device36 of a computer or other suitable device operated thereby and having anopposite input connection .37.

The switch segment 28 is connected by an electrical 2,987,634 PatentedJune 6, 1961 ice 2 conductor 38 to the high output range end of theresistor element 14, While the switch segment 30 is connected by anelectrical conductor 40 to the low range output end of the resistorelement 14.

The rotary contact arm 7 and switch arm 32 are driven by shafts 42 and44, respectively, through a main drive shaft 46 and gearing 48 by asuitable power source, actuator or reversible motor means 50 operativelycontrolled by suitable means not shown. Also, driven by gearing 52 fromthe gearing 48, is a shaft 54 driving the rotary contact arm 20. Thegearing 52 is of a high ratio relative to the gearing 48 and such as tocause the necessary rotation of the shaft 54 and arm 20 relative to theshafts 46, 42 and 44 and arms 7 and 32 so as to effect the desiredoperation.

Operation In the operation of the system shown by the drawing, thepotentiometer 1 is arranged so as to transmit a function from, forexample, units 0-10 and potentiometer 12 is arranged so as to transmit apart of such function between the units 4 to 6. Starting then at thegrounded end or zero point, the contact arm 7 of the potentiometer 1 maybe considered at the low end of its travel (arrows indicate direction oftravel of the arms 7, 20 and 32, in the developing of output valuesindicative of units 0 to 10) recording an output of zero.

In the initial range of operation, the switch arm 32 of the rotaryswitch .26 is arranged to close switch contact segment 30, while thecontact arm 20 of the potentiometer 12 could be anywhere, since theoutput of this potentiometer 12 is controlled by the position of theswitch arm 32 of the rotary switch 26, which in closing contact segment30 is set at a predetermined output value indicative of the unit 4 asset by the resistance 16 in its fixed relation to the resistance ofelement 14 and resistance 18 and is connected to the contact segment 30by the conductor 40. Thus, the output to the device 36 is the same as ifthe contact arm 20 of the potentiometer 12 were at its lower limit solong as the switch arm 32 remains in a closing relation with the contactsegment 30.

However, as the input drive continues to rotate the contact arm 7, thepotentiometer 1 is transmitting its output to the device 10 startingwith unit 0 until the potentiometer 1 develops an output indicative ofthe unit 4 and at which point the contact arm 20 of the potentiometer 12is at a point on the variable resistor 14 providing an output indicativeof the unit 4 and at which point the rotary switch arm 32 issimultaneously adjusted by the input drive to a point closing thecontact segment 24 and thereafter opening the contact segment 30.

The arrangement of the switch arms 20 and 32 is such that prior to theclosing of the contact segment 24 by the arm 32, the arm 20 makescontact with a contact surface 33 providing an extended part of theresistor element 14 and preceding the connection of resistor 16 to theelement 14. The voltage applied along contact surface 33 is the same asthat applied at the point where resistor 16 and element 14 meet givingthe required voltage value of unit 4.

Thus upon the arm 32 making contact with segment 24 and thereafteropening contact segment 30, the arm 20 passes along the contact surface33 and simultaneously passes to the point where resistor 16 and element14 meet at the instant contact arm 32 breaks away from segment 30 andresulting in a smooth transition from unit 4 to values up to the valueof unit 6 as the arm 20 moves along the resistor element 14.

As long as the rotary switch arm 32 remains in closing relation with thecontact segment 24, the output of the potentiometer 12 starting at avalue indicative of the unit 4 will be applied to the device 36. Thecontact arms 7 and 20 and the switch arm 32 are driven in timed relationby the input drive and the arrangement is such that when the output ofthe potentiometers 1 and 12 reaches an output value indicative'of theunit 6, the rotary switch arm 32 closes contact segment 28 andthereafter opens contact segment 24, whereupon the output to the device36 is at a predetermined value indicative of the unit 6 as set by theresistance 18 in its fixed relation to the resistance of element 14 andresistor 1'6 connected to the contact segment 28 by the conductor 38 andthrough the switch arm 32 and conductor 34 to the device 36.

The arrangement of the switch arm 32 and contact arm 20 is such thatimmediately prior to the closing of the contact segment '28 by the arm32, the arm 20 is at the point where resistor element 14 and resistor 18meet. Thereafter upon the switch arm 32 making contact with segment 28,the arm 20 moves along a contact surface 35 provided as an extension ofresistor element 14and thereafter arm 32' opens contact segment 24. Thevoltage applied at the contact surface 35 is the same as that applied atthe point where the elements 14 and resistor 18 meet giving the requiredvoltage value of unit 6.

Thus in th e reverse operation, upon the arm 32 first making contactwith segment 24 and thereafter opening contact segment 28, the arm 20passes along the contact surface 35, and simultaneously passes to thepoint where resistor 18 and element 14 meet at the instant contact arm32 breaks away fromsegment28 so as to result in a smoothtransition fromunit 6 'to values approaching the value of unit 4 as the arm 20 movesalong the resistor element 14. I V

Continuedrotation'of thecontact arm 7 by the input drive willcause thepotentiometer 1 to transmit outputs to the device ltl'indicative or theunit values of 6 up to 10, but the contact arm 20 coul d be anywhere,:since the outpiit supplied to the device 36 is controlled by the switcharm 32 in closing the contact segment 28 so as topro'vide any output ata predetermined value indicative of theiunit 6 during the range ofadjustment of the potentiometer '1 providing output values indicative ofunits'6 to 1O. Thus, the switch arm 32 in closing contact segment 28provides an output the same as if the contact arm 20 of thepotentiometer 12 was adjusted to the upper p Although only oneembodiment of the invention has been illustrated and described, variouschanges in the form and relative arrangements 6f the parts, which willnow a'p'pe'ar'to those skilled'in the art may'be'ma'de without departingfrom the scope of the invention. Reference is, therefore, to be had'tothe appended claims for a definition of'the limits of the invention.

What is claimed is:

1. The combination comprising a first variable resistance means, asecond variable resistance means, means for energizing the first andsecond variable resistance means, meansfor drivingthe first and secondvariable resistance means in timed relation and at different speedratios 'toprovide varying electrical outputs therefrom, switch means forcontrolling the output of the first variable resistance means, meansoperably connecting the driving means to the switch means to selectivelyrenderthe output of the first variable resistance means 'efiective onlyduring a predetermined limited operating range'and within a portion of afull range of operation of the's'econd'variable resistance means so thatupon a function being transmitted by the output from the secnd variableresistance means within said portion of the full operating range thereofthe output of the first variable resistance means may transmit a part ofsaid function within the limited range of operation rendered efiectiveby said switch means. V

2. The combination comprising first variable electrical. outputtransmitting means, second variable electrical output transmittingmeans, third means for controlling the output of the first means, meansfor driving said first, second and third means in timed relation so asto cause said third means to selectively render the electrical outputfrom said first means effective only during a predetermined limitedoperating range within less than a full range of operation 'of thesecond means so that upon a function being transmitted by the outputfrom the second means within said limited operating range the output ofthe first means may transmit a part of said function within the range ofoperation rendered effective by said third means.

3. The combination comprising a first potentiometer for effecting afirst variable electrical output, said first potentiometer including avariable resistor element and a rotary contact arm cooperating with thevariable resistor element, a second potentiometer for effecting a secondvariable electrical output, said second potentiomet'er including avariable resistor element and a rotary contact arm cooperating with thevariable resistor element, a source of electrical energy, means forconnecting the source of electrical energy across the variable resistorelement of said first potentiometer, other means for connecting thesource of e-lectricalenergy across the variable resistor element of saidsecond potentiometer, said other connecting means including a firstfixed resistor element and a second fixed resistor element connected atopposite ends of the variable resistor element of said potentiometer,switch means including first, sec- 0nd and third contact segments and arotary switch arm for selectively contacting said contact segments,motor means, means for drivingly connecting the motor means to therotary contact arm of said first potentiometer and the rotary switch armof said switch means so as to effectively drive the last two arms inunison, high ratio gearing means for drivingly connecting said motormeans to the rotary contact arm of said second potentiometer so as toeffectively drive the'last mentioned rotary contact arm in timedrelation with and at a higher speed ratio than the rotary contact arm ofsaid firstpotentiomete'r, first means for electrically connecting therotary contact arm of said first potentiometer to a device operativelycontrolled by an entire range of variable electrical output'from saidfirst potentiometer, second means for electrically connecting the rotarycontact arm of said second potentiometer to the first contact segment ofsaid switch means, third means for electrically conmeeting said rotaryswitch arm to another device operatively controlled by thevariable-electrical output from said second potentiometer solong as saidrotary switch arm remains in a contacting relation with said firstcontact segment, fourth means for electrically connecting the secondcontact segment to one end of the variable resistor element of thesecond potentiometer, fifth means for electrically connecting the thirdcontact segment to the opposite'end of the variable resistor element ofthe second potentiometer, said other device being operatively controlledthrough said switch'meansby the variable electrical output from saidsecond potentiometer only over a part of the entire output range of thefirst potentiometer so that upon a function being transmitted to thefirst mentioned device by an output from the first potentiometer withinsaid part'of' the entire output range thereof the output of the 'secondpotentiometer may transmit a part ofsaid function to the other deviceupon being rendered effective by the rotary contact arm selectivelycontacting the first contact segment of the switch means, While theselective contacting of said second and third contact segments by therotary contact arm of the switch means renders the first and secondfixed resistor elements eifective respectively to provide therethroughelectrical outputs to control the operation of said other device. p c

4. The combination defined'by claim 3 in whichthe variable resistorelement of the second potentiometer in- 5 6 cludes contact surfaceportions at opposite ends thereof to and from contacting relation withthe first contact to be contacted by the rotary contact arm of thesecsegment and one of the other contact segments of the 0ndpotentiometer so as to effect a smooth transition i h means between thecontrolling electrical outputs for said other device upon the rotaryswitch arm of the switch moving 5 No references cited.

